Confederate raider Adam R. Johnson took a 35-man force northeast about 10 miles from Henderson, Kentucky, on the night of the 17th. Crossing the Green River, a peninsula, and the Ohio River, at 10:00 A.M. the next day, his unit split. 24 men, led by scout Robert M. Martin, crossed the Ohio into Indiana east of Newburgh to create a diversion, and 8 waited at the river across from the town. Johnson and 2 others took a boat over and seized the lightly guarded 2-story brick Union arsenal at the riverside. Martin's men were to work their way into town, cover the removal of arsenal guns to skiffs, then cross the whole force back into Kentucky before Union troops could arrive from nearby Evansville.
Townspeople, seeing the arsenal seized, ran to a nearby hotel and armed themselves. Confident of Martin's timely arrival, Johnson marched into the hotel's lobby, ordered all to disarm, took the local Union commander prisoner, and as Newburgh Home Guards gathered to run off the Confederates, he called on them to look across the river. The 8 raiders left behind 2 manned "cannon", actually lengths of stovepipe laid across wagon wheels and axles. Their appearance, at a distance, convinced outraged townspeople to heed Johnson's threat to "shell this town to the ground". This escapade earned Johnson the nickname "Stovepipe".
As the last load of guns was being feeried across the Ohio, a Union gunboat and troop transport appeared unexpectedly. They intended to move downriver, round the peninsula, and where the Green River empties into the Ohio, block the Confederate route to Kentucky. Johnson and 2 Confederates raced over the peninsula to the mouth of the Green River and fired on the vessels before they deployed to prevent the crossing. Two Union soldiers hit by buckshot in this exchange constituted the only casualties on either side in the raid. Believing that a large number of Confederates faced them, the boats lobbed shells at the riverbank, then withdrew. Johnson's men passed over unmolested and returned to Henderson.
Indiana Gov. Oliver P. Morton, fearing more Confederate incursions on home soil, wired Washington for reinforcements. Over the next days, Union cavalry crossed into Kentucky, made piecemeal attacks on portions of Johnson's force, and occupied several border towns.